by Michael Lopresto
When it comes to explaining human cognition and human uniqueness, everyone seems to think that nature and nurture constitute a false dichotomy. Both nature and nurture work together harmoniously to contribute to the cognitive traits that make humans profoundly different to every other animal on the Earth. Unlike every other animal on Earth, humans are uniquely flexible; we have inhabited every kind of environment, engaged in intergenerational social learning, cooperated with those outside of our immediate group, accurately described things we'll never directly observe, and much more. Humans are cognitively flexible, behaviourally flexible, communicatively flexible and representationally flexible. Representational systems employed by humans are open-ended and unprecedented in the animal kingdom: natural languages like English and Chinese, artificial languages like predicate logic, formal languages like those in mathematics, pictures, diagrams, weather maps are all but a few of the representational systems employed by humans (not to mention mental representations, which are likely to be analogues of the aforementioned systems).
One of the central questions of cognitive science is explaining how humans acquire cognitive traits, including ones that contribute to human uniqueness. Is the trait for language innate or learned? Is the trait for mental time travel (the ability to experience one's past or future) innate or learned? Is the trait for moral reasoning innate or learned? And so forth.
Nativists are those who say that lots of cognitive traits are innate, and empiricists are those who say that very few cognitive traits are innate. The nativism/empiricism distinction is not to be confused with the rationalism/empiricism debate of early modern philosophy. That debate was primarily over epistemology, while the contemporary debate is primarily over psychology. However, questions of epistemology and psychology were systematically conflated, as Kant and others pointed out, and we ought to be careful not to conflate the same questions now. Even so, there are fairly clear links between the two questions. The rationalists of early modern philosophy, like Descartes and Leibniz, argued that a great many cognitive traits were innate, and the empiricists of that era, like Locke and Hume, argued that very few cognitive traits were innate. (Although those philosophers spoke in terms of “innate knowledge” and “innate ideas”—phrases that certainly need careful interpretation).
However, the question “Is cognitive trait X innate or learned?” presupposes that the concepts INNATE and LEARNED are somewhat well defined.[*] (I take it for granted that the concept COGNITIVE TRAIT is uncontroversial, i.e. phenotypic traits relating to things like thinking, inference, perception, intelligence, and so forth.) Our question certainly doesn't presuppose that for any cognitive trait it's all or nothing; totally innate or totally learned, or even totally acquired through environmental interaction.
